A study of the effect of methane and carbon dioxide concentration on gas amplification in argon based gas mixtures

Proportional counter gas amplification has been studied for argon based gas mixtures with methane and carbon dioxide as the quenching agent. Measurements of gas gain have been made using coaxial proportional tubes with different wire radii over a wide range of chamber voltages and pressures. The reduced gain function was found to be dependent on the reduced field E a P , and the fraction of the quenching minority gas and approximately independent of the choice of quencher in most of the proportional region. The full data sample for the ten different gas mixtures can be described by a function with only nine parameters.